Semiconductor device

ABSTRACT

In a semiconductor device of a stacked structure type having a control chip and a plurality of controlled chips, wherein the control chip allocates different I/O sets to the respective controlled chips and processes the I/O sets within the same access cycle, the controlled chip close to the control chip and positioned to a lower position in the stacked structure has I/O penetrating through substrate vias connected to penetrating through interconnections. The penetrating through interconnections are extended to an upper one of the controlled chips that not use the penetrating through interconnections and, as a result, all of the penetrating through interconnections have the same lengths as each other.

This is a Continuation of application Ser. No. 12,838,028 filed Jul. 16,2010, claiming priority based on Japanese Patent Application No.2009-176263 filed Jul. 29, 2009, the contents of all of which areincorporated herein by reference in their entirety.

This application is based upon and claims the benefit of priority fromJapanese patent application No. 2009-176263, filed on Jul. 29, 2009, thedisclosure of which is incorporated herein in its entirety by reference.

FIELD OF THE INVENTION

This invention relates to a semiconductor device incorporating DRAM orother chips and, in particular, relates to a semiconductor device formedby stacking a plurality of chips.

DESCRIPTION OF RELATED ART

As this type of a semiconductor device, JP-A-2004-327474 (PatentDocument 1), which corresponds to US Patent Application Publication No.US 2004/0257847 A1, describes a semiconductor device which forms amemory module or system of a stacked structure having an interposerboard, an IO chip mounted on the interposer board, and a plurality ofDRAM chips stacked together on the IO chip. In this stacked structure,the DRAM chips and the IO chip are connected together throughpenetrating through electrodes formed within via holes.

Specifically, in the DRAM chips of the memory module described in PatentDocument 1, a plurality of penetrating through electrodes formed in thevia holes are provided for transferring data signals and data masksignals accompanying the data signals together with interconnectionswhich are electrically connected to the penetrating through electrodesand which are located between adjacent ones of the chips. Herein, acombination of the penetrating through electrodes and theinterconnections may be called penetrating through substrate vias.

The semiconductor device of this structure is advantageous in thatpenetrating through substrate vias between the plurality of DRAM chipscan be shortened and only the IO chip may have a DLL which consumes alarge current.

Herein, it is to be noted in the instant specification that thepenetrating through substrate vias formed through though-silicon viaholes may be called through-silicon vias (TSVs), as may be recently usedin this technical field.

JP-A-2009-10311 (Patent Document 2), which corresponds to US PatentApplication Publication No. US 2009/0001543 A1, describes a stackpackage having a structure in which a plurality of semiconductor chipsare stacked on a board and the plurality of semiconductor chips areconnected together through through-silicon vias which will beabbreviated to TSV hereinbelow.

SUMMARY OF THE INVENTION Problem to be Solved by the Invention

In the memory system described in Patent Document 1, a memory controller(chip set denoted by 402 in FIG. 38 of Patent Document 1) is providedseparately from the stacked IO chip and DRAM chips and is mounted on amotherboard. The chip set and the IO chip are connected together througha system data bus (disclosed in Patent Document 1). Specifically, thememory system disclosed in Patent Document 1 is formed by a control chipequipped with the controller and controlled chips, such as the stackedDRAM chips and IO chip controlled by the controller. Thus, the controlchip is spatially separated from the controlled chips.

Disclosure of Patent Document 2 is directed only to the stacked packageas controlled objects which are to be controlled by a controller and isnever directed to a controller or a control chip that controls thecontrolled objects or the controlled chips.

At any rate, either Patent Document 1 or Patent Document 2 discloses orsuggests nothing about a problem caused by interconnections between acontrol chip and controlled chips controlled by the control chip. Thatis, either Patent Document 1 or Patent Document 2 considers nothingabout shortening interconnections between a control chip incorporating acontroller and controlled chips controlled by the controller.

Means for Solving the Problem

This invention seeks to solve one or more problems caused to occur inconnection with the stack package.

Effect of the Invention

According to this invention, when data signal DQ and data strobe signalDQS/B interconnections are formed by the penetrating through substratevias, it is possible to minimize the skew between thoseinterconnections. Further, when address, command, and clockinterconnections are formed by the penetrating through substrate vias,it is also possible to minimize the skew between the address and clockinterconnections and the skew between the command and clockinterconnections.

Further, when the controlled chips are divided into a plurality ofgroups and the penetrating through substrate vias are commonly used bythe controlled chips of the respective groups, it is possible to reducethe load of the interconnections as compared with the case where thepenetrating through substrate vias are not commonly used.

BRIEF DESCRIPTION OF THE DRAWINGS

The above features and advantages of this invention will be moreapparent from the following description of certain preferred embodimentstaken in conjunction with the accompanying drawings, in which:

FIG. 1 is a diagram showing the theoretical structure of a semiconductordevice according to a first embodiment of this invention;

FIG. 2 is an interconnection diagram for theoretically explaining asemiconductor device according to a second embodiment of this invention;

FIG. 3 is a diagram for explaining the interconnection impedanceaccording to the second embodiment of this invention;

FIG. 4 is a diagram showing the three-dimensional structure of thesemiconductor device shown in FIGS. 2 and 3;

FIG. 5 is an equivalent circuit diagram of the semiconductor deviceshown in FIG. 4, wherein an equivalent circuit at a specific data signalpenetrating through via portion is shown;

FIGS. 6A, 6B, and 6C are diagrams more specifically showing thestructure of a SDRAM chip used in the semiconductor device shown in FIG.5;

FIGS. 7A and 7B are diagrams for explaining SDRAM chips used in asemiconductor device according to a third embodiment of this invention;

FIGS. 8A, 8B, and 8C are diagrams for explaining a semiconductor deviceaccording to a fourth embodiment of this invention and SDRAM chips usedin the semiconductor device;

FIGS. 9A and 9B are circuit diagrams showing a RLWLON generation circuitused in the semiconductor device shown in FIGS. 8A to 8C; and

FIG. 10 is an operation waveform diagram for explaining the operation ofthe RLWLON generation circuit shown in FIGS. 9A and 9B.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

This invention will be now described herein with reference toillustrative embodiments. Those skilled in the art will recognize thatmany alternative embodiments can be accomplished using the teachings ofthis invention and that this invention is not limited to the embodimentsillustrated for explanatory purposes.

Referring to FIG. 1, the theoretical structure of a semiconductor deviceaccording to a first embodiment of this invention will be described. Theillustrated semiconductor device comprises a logic LSI chip 20 as acontrol chip and a plurality of SDRAM chips as controlled chips stackedon the logic LSI chip 20. The control chip may be also called a masterchip (or active chip) while each controlled chip is a slave chip (orpassive chip). For example, the semiconductor device comprising themaster chip and the slave chips has a system-in-package structure inwhich those chips are assembled in layers and integrally packaged. Thestructure shown in FIG. 1 is specified by a structure obtained bycombining the so-called COC (Chip On Chip) technology and TSV (ThroughSilicon Via) technology, as mentioned in detail with reference to FIG.4. In the figure, external terminals (not illustrated) of thesemiconductor device with the structure shown in FIG. 1 are disposed onthe lower side of the logic LSI chip 20. The external terminals areconnected to the logic LSI chip 20. I/O signal lines penetrating throughthe controlled chips, which will be described later, are connected tothe logic LSI chip 20 and are not directly connected to the externalterminals.

FIG. 1 shows an example in which 16 SDRAM chips D0 to D15 each having amemory capacity of 1 Gbit are stacked on the logic LSI chip 20 operableas the control chip. Each of the illustrated SDRAM is a DDR (Double DataRate) 3 synchronous dynamic random access memory.

The 16 SDRAMs D0 to D15 are divided into a first group including theSDRAMs D0, D1, D2, . . . D6, D7 and a second group including the SDRAMsD8, D9, . . . D14, D15. The first and second groups are alternativelyselected by a first clock signal CS0CK0 and a second clock signalCS1CK1, respectively, and each output from the control chip (masterchip) 20, which will be described later. Hereinafter, the first andsecond groups each may also be referred to simply as a “group” or as a“chip selection group”.

In the illustrated example, the SDRAMs D0 and D8 form a first DRAM setlocated closest to the logic LSI chip 20, then, subsequent pairs of theSDRAMs D1 and D9, D2 and D10, D3 and D11, D4 and D12, D5 and D13, D6 andD14, and D7 and D15 form second to eighth DRAM sets, respectively. Asseen in FIG. 1, the SDRAM D15 of the eighth DRAM set is disposed at aposition farthest from the logic LSI chip 20. The first to eighth DRAMsets are accessed in parallel by the control chip (master chip) 20 sothat a data transfer rate of 51.5 Gbyte/sec is achieved, which will bedescribed later. Hereinafter, the first to eighth DRAM sets each mayalso be referred to simply as a “set” or as a “DRAM set”.

The SDRAMs D0 to D15 have the same penetrating through substrate vias,namely, Through-Silicon Vias (TSV) structure, i.e. the same pinstructure as one another. Specifically, it is assumed that the SDRAMs D0to D15 each have a total of 382 TSVs including 256 data signal (DQ)penetrating through substrate vias (TSVs), 32 data mask (DM) penetratingthrough substrate vias (TSVs), 64 data strobe signal (DQS/DQSB)penetrating through substrate vias (TSVs), 14 address penetratingthrough substrate vias (A0 to A13) (TSVs), 3 bank address penetratingthrough substrate vias (BA0 to BA2) (TSVs), 3 command signal penetratingthrough substrate vias (TSVs) (/RAS (RASB), /CAS (CASB), /WE (WEB)), and10 control signal penetrating through substrate vias (TSVs) (CS0, CS1,CKE0, CKE1, CK0, CK1, /CK0, /CK1, ODT0, ODT1). It is needless to saythat power supply penetrating through substrate vias (TSVs) are alsoprovided in addition to the above-mentioned TSVs. At any rate, the term“via” or “vias” may be considered as a combination of a penetratingthrough electrode and an interconnection connected to the penetratingthrough electrode.

A data signal (DQ), a data mask signal (DM), data strobe signals(DQS/DQSB), an address (A0-A13), a bank address (BA0-BA2), commandsignals (/RAS (RASB), /CAS (CASB), /WE (WEB)), and control signals (CS0,CS1, CKE0, CKE1, CK0, CK1, /CK0, /CK1, ODT0, ODT1) are all well-knownsignals for controlling the DRAM functions. CK0, CK1, /CK0, and /CK1 areso-called system clocks for use in communication between the controlchip (master chip) and the controlled chips (slave chips) and thus thesechips are of the synchronous type.

Herein, the penetrating through substrate vias, namely, through-siliconvias (TSVs) each continuously penetrating through the SDRAMs D0 to D15are called continuous TSVs.

Each SDRAM has an 8-bank structure and outputs a 32-bit data signal inparallel. The 256 data signal (DQ) TSVs are each shared by theabove-mentioned two groups (chip selection groups). In this case, sinceeach DDR3 SDRAM normally gives a transfer rate of 1600 Mbps per pin,each group can achieve a data transfer rate of 1600 Mbps×32×8 (DRAMsets)=409.6 Gbit/sec=51.5 Gbyte/sec. Of the two groups (chip selectiongroups), the first group (first controlled chips) iscommunication-controlled at a first access cycle by the first chipselection signal (first clock signal CS0CK0) output from the controlchip 20 while the second group (second controlled chips) iscommunication-controlled at a second access cycle by the second chipselection signal (second clock signal CS1CK1) output from the controlchip 20. Since the first and second groups are mutually exclusivelycontrolled by the control chip 20 at the first and second access cycles,each of the TSVs corresponding to one I/O bit is shared by the first andsecond groups. As shown by solid lines in FIG. 1, the continuouspenetrating through type vias, namely, continuous type TSVs are providedeach penetrating through all the SDRAMs from the SDRAM D15 to the SDRAMD0. Therefore, the continuous type TSVs respectively forming the datasignal (DQ) TSVs and the data strobe signal (DQS/DQSB) TSVs aresubstantially equal in length to each other. Further, the continuoustype TSVs respectively forming the address, command, and clock TSVs arealso substantially equal in length to each other.

Referring to FIG. 2, the structure of a semiconductor device accordingto a second embodiment of this invention is illustrated. Also in thisembodiment, as in the first embodiment shown in FIG. 1, it is assumedthat pairs of SDRAMs D0 and D8 to SDRAMs D7 and D15 of 8 DRAM sets arestacked on a logic LSI chip 20. It is assumed, however, that each of theSDRAMs D0 to D15 is a 2 Gbit DDR3 SDRAM.

The logic LSI chip 20 shown in FIG. 2 comprises a clock generator 201, alogic control circuit (controller) 203, a DLL circuit 205, aninput/output circuit 207, and a VDDQ conversion circuit 209. From theVDDQ conversion circuit 209, a memory-driving main power supply voltageVDDQ is applied not only to the input/output circuit 207 and the logiccontrol circuit 203 of the logic LSI chip 20, but also to the SDRAMs D0to D15 stacked on the logic LSI chip 20.

The clock generator 201 supplies a first clock signal CS0CK0 to theSDRAMs D0 to D7 (which belong to first controlled chips) forming a firstgroup (chip selection group) and further supplies a second clock signalCS1 CK1 to the SDRAMs D8 to D15 (which belong to second controlledchips) forming a second group (chip selection group). Further, the clockgenerator 201 also has a function of outputting command signals RASB,CASB, and WEB. The signals RASB, CASB, and WEB specify one command.

The first and second clock signals CS0CK0 and CS1 CK1 are supplied tothe SDRAMs D0 to D15 through the clock TSVs while the command signalsare supplied to the SDRAMs D0 to D15 through the command TSVs. Herein,the first clock signal CS0CK0 does not need to be actually supplied tothe uppermost SDRAM 15 belonging to the second group (chip selectiongroup), but in this embodiment, as shown by a broken line in FIG. 2, theTSV for the first clock signal CS0CK0 also extends to the uppermostSDRAM 15 and, as a result, the TSV for the first clock signal CS0CK0 hassubstantially the same length as the TSV for the second clock signal CS1CK1. That is, the interconnection formed by the TSV for the first clocksignal CS0CK0 includes an unused and redundant interconnection portion(hereinafter referred to as an “unused and redundant interconnection”)in terms of necessary connection.

The logic control circuit 203 provided in the logic LSI chip 20 outputsa 3-bit bank address signal BA0-2 and a 14-bit address signal A0-13 andoperates as a controller that sends and receives data signals DQ betweenitself and the input/output circuit 207. The logic control circuit 203has a function similar to that of a SSTL (Stub Series Terminated Logic)DDR controller, but this embodiment differs from the SSTL chip in thatthe logic LSI chip 20 having such a controller function is stacked alongwith the SDRAMs D0 to D15. Accordingly, the logic LSI chip 20 haselectrodes electrically connected to the continuous TSVs provided in theSDRAMs D0 to D15.

Each input/output circuit 207 sends and receives 32-bit width datasignals DQ between itself and the SDRAMs D0 to D15, respectively, andthus sends and receives parallel data signals DQ of 256-bit width intotal. The data signal DQ is transmitted or received as an I/O datasignal. The first DRAM set is allocated with a first I/O group (×32 DQsignal bits) and the second DRAM set is allocated with a second I/Ogroup (×32 DQ signal bits). The third to eighth DRAM sets are allocatedwith third to eighth I/O groups, respectively. These eight I/O groupsare accessed in parallel by the control chip (master chip) 20 so thatthe above-mentioned data transfer rate of 51.5 Gbyte/sec is achieved.That is, the DRAM sets defined by the I/O groups determine the datatransfer rate. In other words, they define the transfer band width whichrepresents the number of I/O transfer bits that are simultaneouslycommunicated. As the number of DRAM sets increases, the transfer bandwidth increases and thus the data transfer rate increases. As the numberof I/O bits forming each I/O group increases, the transfer band widthincreases and thus the data transfer rate increases. On the other hand,the chip selection groups determine the memory capacity value. As thenumber of chip selection groups increases, the memory capacity valueincreases.

Therefore, in FIG. 1, it is to be noted that the number of DRAM setsstacked on the control chip (master chip) 20 represents the transferband width while the number of chip selection groups in each DRAM setrepresents the storage capacity. By controlling the controlled chips ofeach of the first and second groups at the same access cycle, thecontrol chip 20 communicates information of the predetermined I/O bandwidth (256 data signal (DQ) bits, i.e. ×256 I/O bits) between itself andthe controlled chips.

Thus, the control ship 20 is communicable with the controlled chips ofthe first and the second groups by the use of the predetermined numberof I/O bits, namely, 256 bits in the illustrated example.

The 3-bit bank address signal BA0-2 and the 14-bit address signal A0-13are supplied to all the SDRAMs D0 to D15 through the address TSVs.

As is clear from the above description, the TSVs for the first andsecond clock signals, the TSVs for the command signals, and the TSVs forthe address signals are substantially equal in length to each other.

The SDRAM D0 (first DRAM set) and the input/output circuit 207 of thelogic LSI chip 20 are connected to each other through the 32 data signalDQ TSVs as indicated by ×32 (first I/O group) in FIG. 2. Theinput/output circuit 207 includes interface circuits such as bufferscorresponding to the SDRAM chips, respectively, so that data signals DQare sent and received between the SDRAM D0 and the logic control circuit203 through the corresponding interface circuit. Each interface circuitmay have a parallel-serial conversion circuit. The data signal DQ TSVsbetween the SDRAM D0 and the logic LSI chip 20 pass through the SDRAMsD8, D1, D9, . . . , D14, D7 to extend to the uppermost SDRAM D15,thereby forming the continuous type TSVs. This means that the datasignal DQ TSVs for the SDRAM D0 each include an unused and redundantinterconnection from the SDRAM D1 (second DRAM set) to the SDRAM D15(eighth DRAM set). As will be described later, the data signal DQ TSVsfor the SDRAM D0 are also used by the SDRAM D8 (first DRAM set). Thatis, the data signal DQ TSVs for the SDRAM D0 are commonly used by thefirst DRAM set (SDRAM D0 and SDRAM D8). Specifically, the logic LSI chip20 and the SDRAM D0 are connected to each other through first datasignal DQ TSVs and the SDRAM D0 and the SDRAM D8 are connected to eachother through second data signal DQ TSVs electrically identical to thefirst data signal DQ TSVs. The above-mentioned unused and redundantinterconnections or vias related to the first DRAM set extend to theother DRAM sets (second to eighth DRAM sets). However, the data signalDQ TSVs (×32) used by the first DRAM set are not used by the second toeighth DRAM sets and thus are unused and redundant interconnections forthose DRAM sets in terms of necessary connection.

Likewise, the data signal DQ TSVs (second I/O group) for the SDRAM D1(second DRAM set) also extend from the input/output circuit 207 of thelogic LSI chip 20 to the SDRAM D15 through the SDRAMs D0, D8, D1, D9, .. . , D7. Therefore, it is seen that the data signal DQ TSVs for theSDRAM D1 include unused and redundant interconnections corresponding tothe first and third to eighth DRAM sets. This applies to the subsequentSDRAMs. The data signal DQ TSVs for the SDRAM D7 are provided betweenthe input/output circuit 207 of the logic LSI chip 20 and the SDRAM D7.The data signal DQ TSVs for the SDRAM D7 are also formed by 32 TSVs andare commonly used by the SDRAMs D7 and D15. In this manner, all the datasignal DQ TSVs form the continuous type TSVs connected between the logicLSI chip 20 and the uppermost SDRAM D15 and are substantially equal inlength to each other.

Herein, taking the SDRAM D0 as an example, the structure of the SDRAMchip used in this embodiment will be described. The illustrated SDRAM D0comprises, in addition to the above-mentioned TSVs, a DRAM array 301having a memory capacity of 2 Gbit, a command decoder 303, an addressbuffer 305, an X-decoder 307, a Y-decoder 309, a DLL circuit 311, and aparallel-serial conversion circuit 313.

The command decoder 303 of the SDRAM D0 belonging to the first group(chip selection group) decodes command signals RASB, CASB, and WEB sentfrom the logic LSI chip 20.

On the other hand, a bank address signal BA0-2 and an address signalA0-13 from the logic control circuit 203 are given to the address buffer305. The address buffer 305 outputs address signals AX0-13 and AY0-9 tothe X-decoder 307 and the Y-decoder 309, respectively. In response tothe address signals AX0-13 and AY0-9 given to the X- and Y-decoders 307and 309, the DRAM array 301 inputs and outputs 128-bit (×128) datasignals in parallel between itself and the parallel-serial conversioncircuit 313. The input/output operations of the 128-bit data signals areperformed under the control of a command from the command decoder 303and clocks from the DLL circuit 311.

The parallel-serial conversion circuit 313 sends and receives ×128-bitparallel data signals between itself and the DRAM array 301 and furthersends and receives 32-bit (×32) parallel data signals between itself andthe logic LSI chip 20. That is, the parallel-serial conversion circuit313 has a function to convert a ×128-bit data signal into ×32-bit datasignals and to convert ×32-bit data signals into a ×128-bit data signal.

In the illustrated structure, since the data signal DQ and data strobesignal DQS/B TSVs for all the DRAM sets corresponding to the respectiveI/O groups can be made substantially equal in length to each other, theskew between data signals DQ and data strobe signals DQS/B can beminimized. This structure (equi-length interconnections) is veryimportant in the stacked structure in which the plurality of DRAM setsare stacked in sequence with respect to the controller chip. This isbecause, in this embodiment, each I/O group is formed by ×32 DQ signalbits and the controller chip can perform communication control of theplurality of I/O groups (×256 DQ signal bits) with a singlesynchronization signal and with high accuracy. Since the address,command, and clock signal TSVs can also be made substantially equal inlength to each other, it is also possible to minimize the skew betweenaddress and clock signals and between command and clock signals.

As described above, according to the first and second embodiments ofthis invention, it is possible to form a semiconductor device in which acontrol chip (logic LSI chip 20 in FIGS. 1 and 2) and a plurality ofcontrolled chips (SDRAM chips in FIGS. 1 and 2) are stacked together bythe use of the so-called TSV technology.

Herein, consideration is given to the case where two controlled chipsare stacked on a control chip and are connected to the control chipthrough penetrating through substrate vias, namely, through-silicon vias(TSVs).

For example, a first chip is assumed to be a control chip (master chip)and a second chip (first DRAM set) and a third chip (second DRAM set)are assumed to be controlled chips (slave chips). In addition, it isassumed that the second and third chips are stacked in this order on thefirst chip. First, communications (read/write) of respective I/O groupsare performed between the first control chip and the second and thirdcontrolled chips. In this event, the distance (first impedance) of asignal line connected between respective circuits of the first controlchip and the second controlled chip differs from the distance (secondimpedance) of a signal line connected between respective circuits of thefirst control chip and the third controlled chip so that there aredifferences in signal arrival time and reflected wave quantity (usingthe respective chips as references).

Taking this into account, in the first and second embodiments, it ispointed out that the first and second impedances can be madesubstantially equal to each other by setting the distance of the signalline between the first control chip and the second controlled chip to beequal to the distance of the signal line between the first control chipand the third controlled chip.

It is preferable to take into account that, practically, signal linesformed by through-silicon vias (TSVs) are not necessarily made equal inimpedance to each other due to manufacturing variations in manufacturingprocesses (TSV forming process, bump forming process, and TSV-bumpconnection process). That is, TSVs formed in different manufacturingprocesses may have different impedances due to manufacturing variationsin the manufacturing processes.

Further, it is also preferable to expect that when a plurality of signallines are formed by a plurality of TSVs, the impedance of each signalline may be different from those of the others due to variations ofinherent manufacturing processes.

Moreover, it is also preferable to take into account that it may benecessary to individually adjust ODTs (On-Die Terminations), i.e.termination resistances, connected on respective SDRAM chips dependingon manufacturing variations.

On the other hand, in the case of a well-known surface mount type moduledifferent from the stacked type semiconductor device according to thisinvention, it is usual to form, in the same process, interconnectionsbetween a plurality of chips in a module board. That is, in the surfacemount type module, it is not necessary to consider the difference inimpedance due to the difference in manufacturing process. For example,in the surface mount type module, a plurality of interconnections in themodule board and a plurality of interconnections in the chips aresimultaneously formed in the same process. Therefore, for example, ifthe interconnections are narrowed due to manufacturing variations, theimpedances of all the interconnections uniformly change in the samedirection and thus it is not necessary to consider the difference inimpedance between interconnections that are formed in differentmanufacturing processes.

Referring to FIG. 3, there are shown interconnection impedances in thesemiconductor device according to the second embodiment of thisinvention. Herein, the interconnection impedances in a through-siliconvia (TSVa) for the second clock signal CS1CK1 and a data signal DQ TSVbfor the SDRAM D15 are exemplarily illustrated. The illustratedinterconnection impedances are respectively given by penetrating throughelectrode resistances RVIA and capacitances CVIA in the TSVa for thesecond clock signal CS1CK1 and the data signal DQ TSVb for the SDRAMD15. In FIG. 3, in order to simplify the explanation, the penetratingthrough electrode resistances RVIA and the capacitances CVIA in the TSVafor the second clock signal CS1CK1 and the data signal DQ TSVb for theSDRAM D15 are shown to be equal to each other. When paying attention tothe TSVa for the second clock signal CS1CK1, an equivalent circuitthereof can be given by penetrating through electrode resistances RVIAconnected in series from the SDRAM D0 to the SDRAM D15 and a pluralityof capacitances CVIA each connected between the adjacent penetratingthrough electrode resistances RVIA.

A TSV DQC1 being part of the data signal DQ TSV for the SDRAMs D0 and D8is shared by the SDRAMs D0 and D8. Likewise, a TSV DQC2 being part ofthe data signal DQ TSV for the SDRAMs D1 and D9 is shared by the SDRAMsD1 and D9. Further, a TSV DQC8 is shared by the SDRAMs D7 and D15.Herein, an equivalent circuit of the data signal DQ TSVb including asits part the shared penetrating through electrode DQC8 can be given by aseries circuit having penetrating through electrode resistances RVIAconnected in series from the SDRAM D0 to the SDRAM D15 and a pluralityof capacitances CVIA each connected between the adjacent penetratingthrough electrode resistances RVIA. The penetrating through electrodecapacitance CVIA is actually about 60 pF.

As is clear from FIG. 3, the SDRAM chip located closer to the logic LSIchip 20 has a smaller penetrating through resistance while the SDRAMchip located farther from the logic LSI chip 20 has a larger penetratingthrough resistance. Further, these penetrating through resistancesslightly have variations due to the difference in manufacturing process.

Referring to FIG. 4, the structure of the semiconductor device shown inFIGS. 2 and 3 will be described in more detail. Herein, the structure ofthe data signal DQ TSVs is mainly illustrated and, as is clear from FIG.4, these TSVs form the continuous type TSVs, respectively. As shown inFIG. 4, the 16 SDRAMs D0, D8, D1, D9, D2, D10, D3, D11, D4, D12, D5,D13, D6, D14, D7, and D15 are stacked in this order on the logic LSIchip 20. The SDRAMs D0 to D7 form the first group (first chip selectiongroup) and the SDRAMs D8 to D15 form the second group (second chipselection group). The adjacent two SDRAMs of the first and secondgroups, such as, for example, the SDRAMs D0 and D8, D1 and D9, or D7 andD15, form a SDRAM pair or set (n-th DRAM set) sharing the correspondingdata signal DQ TSVs, i.e. corresponding buses (n-th I/O group).

In order to clarify the above-mentioned sharing relationship, in FIG. 4,a single data signal DQ TSV shared by the SDRAMs D0 and D8 of the firstDRAM set is given by TSVO8 (first I/O set), a single data signal DQ TSVshared by the SDRAMs D1 and D9 of the second DRAM set is given by TSV19(second I/O set), and a single data signal DQ TSV shared by the SDRAMsD7 and D15 of the eighth DRAM set is given by TSV715 (eighth I/O set).As enlargedly shown on the right side in FIG. 4, the upper side and thelower side in the figure of each SDRAM chip are silicon (Si) front andback surfaces, respectively, and through-silicon vias TSVs havepenetrating through interconnections between the front and the backsurfaces and electrodes formed on the front and back surfaces.

As seen from FIG. 4, all the data signal DQ TSVs have the same length ifthere is no variation in manufacturing processes and so on. Further, thedata signal DQ TSVO8 includes a portion shared by the SDRAMs D0 and D8and, in this connection, circuits formed at the front surfaces of theSDRAMs D0 and D8 and the data signal DQ TSVO8 are in a conductive state(i.e. on state). On the other hand, the SDRAMs other than the SDRAMs D0and D8 and the data signal DQ TSVO8 are in a non-conductive state (i.e.off state).

Likewise, the data signal DQ TSV19 and circuits formed at the frontsurfaces of the SDRAMs D1 and D9 are in a conductive state (i.e. onstate) while the data signal DQ TSV19 is not electrically connected tothe SDRAMs other than the SDRAMs D1 and D9. Further, the data signal DQTSV715 and circuits formed at the front surfaces of the SDRAMs D7 andD15 are in a conductive state (i.e. on state).

From this fact, it should be understood that the controlled chipsspecified by the SDRMS D0 to D15 are divided into a first set or groupD0 to D7 and a second set or group D8 to D15 and that the first set ofthe controlled chips D0 to D7 has first ones of the penetrating throughsubstrate vias (namely, through-silicon vias) that are used forperforming communication between the control chip and the controlledchips of the first set and second ones of the penetrating throughsubstrate vias that are used for performing communication between thecontrol chip and the controlled chips of the second set. Likewise, thesecond set of the controlled chips comprises third ones of thepenetrating through substrate vias that are used for performingcommunication between the control chip and the controlled chips of thesecond set and fourth ones of the penetrating through substrate viaswhich are used for performing communication between the control chip andthe controlled chips of the first set.

Moreover, it is to be noted that the first ones of the penetratingthrough substrate vias and the fourth ones of the penetrating throughsubstrate vias are connected to each other and are connected to firstones of the nodes of the control chip corresponding to the first I/Ogroup, to thereby structure a first interconnection. Likewise, thesecond ones of the penetrating through substrate vias and the third onesof the penetrating through substrate vias are connected to each otherand are connected to second ones of the nodes of the control chipcorresponding to the second I/O group, to thereby structure a secondinterconnection. As a result, the first interconnection and the secondinterconnection are substantially equal in length to each other withinthe stacked structure.

This means that the first ones of the penetrating through substrate viasand the fourth ones of the penetrating through substrate vias arearranged at first coordinate positions placed at the same positions oncoordinate defined on the respective controlled chips. Similarly, thesecond ones of the penetrating through substrate vias and the third onesof the penetrating through substrate vias are arrange at secondcoordinate positions placed at the same positions on coordinate definedon the respective controlled chips. At any rate, the first and thesecond interconnections form first and second continuous penetratingthrough type conductors which are perpendicular and straight to thefirst and the second nodes of the control chip.

Referring now to FIG. 5, there is shown an equivalent circuit forspecifically explaining the data signal DQ TSV715 and circuits relatedto TSV715 in the semiconductor device shown in FIG. 4. Herein, thesemiconductor device according to the second embodiment of thisinvention is illustrated and, in this connection, it is assumed that theSDRAMs D0 to D15 include chip switch circuits CS0 to CS15, respectively,for the single data signal DQ TSV715 and that the chip switch circuitsCS15 to CS0 each include later-described compensation resistances.

The chip switch circuits CS15 to CS0 each include two switch elements saand sb each for determining an on/off state with respect to the datasignal DQ TSV715. These two switch elements sa and sb are controlled bya first ROM1 and a second ROM2. For the sake of simplification, adescription will be given assuming that the first ROM1 and the secondROM2 are provided commonly for all the SDRAMs D0 to D15, but each SDRAMmay be provided with a first ROM1 and a second ROM2.

Herein, the DRAM set of the SDRAMs D15 and D7 sharing the data signal DQTSV715 will be explained. The first ROM1 outputs first and second groupindication signals C0SIG and C1SIG indicative of the first and secondgroups (chip selection groups), respectively. The second ROM2 outputs aset indication signal (D715 for the SDRAM D15) indicative of a SDRAMpair forming a set (n-th DRAM set).

In the chip switch circuit CS15 of the SDRAM D15 shown in FIG. 5, theswitch sa which is given the set indication signal D715 and the secondgroup indication signal C1SIG is put in an on (conductive) state. Duringthe on state of the switch sa, the switch sb which is given the setindication signal D715 and the first group indication signal C0SIG is inan off (non-conductive) state.

On the other hand, in the chip switch circuit CS7 of the SDRAM D7,conversely to the SDRAM D15, the switch sa which is given the setindication signal D715 and the second group indication signal C1 SIG isput in an off state. During the off-state of the switch sa, the switchsb given the set indication signal D715 and the first group indicationsignal C0SIG is in an on state.

The other SDRAMs D0 to D6 and D8 to D14 given a logic “0” level as theset indication signal D715 are all in an off state and, as a result, theSDRAMs D15 and D7 can selectively send or receive a data signal DQ to orfrom the logic LSI chip 20 through the data signal DQ TSV715. In thismanner, it is seen that the TSV715 is shared by the SDRAMs D15 and D7.

In the illustrated example, the description has been given assuming thatthe first ROM1 and the second ROM2 generate the above-mentioned groupand set indication signals collectively for all the SDRAMs D15 to D0.However, as described above, each SDRAM may be provided with the firstROM1 and the second ROM2. The group indication signal is a typicalexample of a chip selection group indication signal and the setindication signal is a typical example of a DRAM set indication signal.

In FIG. 5, an equivalent circuit inside the SDRAM D15 is shown and it isassumed that the other SDRAMs D0 to D14 are each given by the sameequivalent circuit as the SDRAM D15. In this connection, the equivalentcircuits of the SDRAMs D0 to D14 are expressed only by circuit elements.

The illustrated equivalent circuit inside the SDRAM D15 comprises aninterconnection resistance R2 in the chip, a chip internal capacitanceC2 such as a capacitance due to pads (pads in FIGS. 6A to 6C) in thechip and an interconnection capacitance, and an interconnectioninductance L1. In this example, the other SDRAMs D0 to D14 are eachexpressed by the same equivalent circuit comprising an interconnectionresistance R2, a chip internal capacitance C2, and an interconnectioninductance L2. The pads are so-called probing pads mainly used when awafer test of the single chip is conducted before an assembly process ofstacking the plurality of chips with the TSV electrodes.

Like in the above-mentioned example, the data signal DQ TSV715 is shownto have penetrating through electrode resistances RVIA and penetratingthrough capacitances CVIA also at the SDRAM portions other than at theSDRAMs D15 and D7.

On the other hand, in FIG. 5, the logic LSI chip 20 is also expressed byan equivalent circuit. The equivalent circuit of the logic LSI chip 20comprises an interconnection resistance R3 in the logic LSI chip 20, acapacitance C3 such as an interconnection capacitance, and aninterconnection inductance L2. The illustrated equivalent circuit of thelogic LSI chip 20 is given by the impedance of a MOS driver in memorywrite. Preferably, the logic LSI chip 20 further has a compensationimpedance for impedance adjustment.

Referring now to FIG. 6A, the SDRAM chips forming the semiconductordevice shown in FIG. 5 will be described in more detail. Herein, thereis shown a plan view of one of the stacked SDRAMs D0 to D15 (e.g. theSDRAM D15). This structure is the same in the other SDRAM chips.

A chip switch circuit CS (index omitted) of the SDRAM chip shown in FIG.6A includes pairs of switch elements SW0 and SW8, SW1 and SW9, SW2 andSW10, SW3 and SW11, SW4 and SW12, SW5 and SW13, SW6 and SW14, and SW7and SW15 that are provided corresponding to the shared data signal DQTSVs, i.e. the continuous type TSV08, TSV19, TSV210, TSV311, TSV412,TSV513, TSV614, and TSV715, respectively. These pairs of switch elementsSW0 and SW8, SW1 and SW9, SW2 and SW10, SW3 and SW11, SW4 and SW12, SW5and SW13, SW6 and SW14, and SW7 and SW15 correspond to the switchelements sa and sb provided in the chip switch circuits CS15 to CS0shown in FIG. 5 although FIG. 5 shows the switch elements sa and sbcorresponding only to the continuous TSV715.

The SDRAM chip shown in FIG. 6A further includes a first ROM1 and asecond ROM2 and has a function to compensate for phase variations amongthe data signal DQ TSVs. Specifically, FIG. 6A shows the connectionrelationship between the data signal DQ TSV08 to TSV715 and the switchelements SW0 to SW15 while FIG. 6B shows the connection relationshipbetween control signal CS0/1 TSVs (herein denoted by VIAC0 and VIAC1,respectively) and switch elements SWC0 to SWC15. Further, FIG. 6C showsthe structure of each of the switch elements SW0 to SW15 and SWC0 toSWC15.

In FIG. 6A, the switch elements SW0 to SW15 respectively connected tothe data signal DQ TSV 08 to TSV 715 on each SDRAM chip are collectivelygiven as a chip switch circuit portion CSWDQ while, in FIG. 6B, theswitch elements SWC0 to SWC15 respectively connected to the controlsignal CS0/1 TSVs VIAC0 and VIAC1 on each SDRAM chip are collectivelygiven as a chip switch circuit portion CSWC.

The data signal DQ TSV08 provided on the upper side in FIG. 6A is apenetrating through electrode shared by the SDRAMs D0 and D8 locatedclosest to the logic LSI chip 20 and the TSVs provided lower in FIG. 6Aare penetrating through electrodes shaped by the SDRAM chips locatedfarther from the logic LSI chip 20. Accordingly, the data signal DQTSV715 provided at the lowermost position in FIG. 6A is a penetratingthrough electrode shaped by the SDRAMs D7 and D15 provided at theuppermost position in FIG. 4. In other words, the data signal DQ TSV08is required to be set in an on state only at the SDRAMs D0 and D8 andlikewise the data signal DQ TSV715 is required to be set in an on stateonly at the SDRAMs D7 and D15.

On the upper side in FIG. 6B, there are shown the switch elements SWC0and SWC8 that are put into an on state in circuits connected to theSDRAMs D0 and D8 and located closest to the logic LSI chip 20 while, atthe lowermost position, there are shown the switch elements SWC7 andSWC15 that are put into an on state in circuits connected to the SDRAMsD7 and D15 and located farthest from the logic LSI chip 20. The switchelements SWC0 to SWC15 are selectively put into an on state according tofirst and second group indication signals C0SIG and C1SIG from the firstROM1 and set indication signals D08 to D715 from the second ROM2 and acontrol signal CS0/1 is supplied to the respective SDRAM chips througheither one of the through-silicon vias (TSVs) VIAC0 and VIAC1 and theselected switch elements.

An output MOS transistor and an input circuit shown in FIG. 6A areso-called I/O circuits (internal circuits) and, in the case of DRAM DQ,a memory cell is connected through the output MOS transistor and theinput circuit. An input circuit shown in FIG. 6B is a so-calledinterface input circuit for transmitting a clock, address, or commandsignal or the like to a logic circuit in the chip.

FIG. 6A will be explained in more detail. First and second groupindication signals C0SIG and C1SIG are given from the first ROM1 to thechip switch circuit portions CSWDQ of the SDRAMs forming the respectivegroups (chip selection groups) and set indication signals D08 to D715are given from the second ROM2 to the chip switch circuit portions CSWDQof the SDRAM pairs forming the respective sets (DRAM sets). In thisexample, when the first and second group indication signals C0SIG andC1SIG are output to the SDRAM chips belonging to the respective groups(chip selection groups), i.e. output to the selected SDRAM chips, thefirst and second group indication signals C0SIG and C1SIG take a logic“1” level. The set indication signal takes a logic “1” level in the caseof the selected set (selected DRAM set) while takes a logic “0” level inthe case of the non-selected set (non-selected DRAM set).

When the SDRAM chip shown in FIG. 6A is used as any one of the SDRAMs D0to D7 forming the first group (first chip selection group), a logic “1”level is given as the first group indication signal C0SIG from the firstROM1 to the switch elements SW0 to SW7 provided in the chip switchcircuit portion CSWDQ.

On the other hand, when the SDRAM chip shown in FIG. 6A is used as anyone of the SDRAMs D8 to D15 forming the second group (second chipselection group), a logic “1” level is given as the second groupindication signal C1SIG from the first ROM1 to the switch elements SW8to SW15 provided in the chip switch circuit portion CSWDQ.

Further, when the SDRAM chip shown in FIG. 6A is used as either one ofthe SDRAM chip pair, for example, the SDRAMs D15 and D7, forming the set(DRAM set), the set indication signal D715 of logic “1” is given to theswitch elements SW15 and SW7 from the second ROM2. Likewise, when usedas either one of the SDRAMs D14 and D6, the set indication signal D614of logic “1” is given to the switch elements SW14 and SW6. This appliesto the subsequent SDRAM pairs. When used as either one of the SDRAMs D8and D0, the set indication signal D08 of logic “1” is given to theswitch elements SW8 and SW0.

Referring to FIG. 6C, the structure of the above-mentioned switchelements SW0 to SW15 will be described. As is clear from FIG. 6C, theswitch elements SW0 to SW15 each comprise a NAND gate that outputs NANDof a group indication signal (given by C) from the first ROM1 and a setindication signal (given by D) from the second ROM2, an inverter thatinverts a NAND gate output, and a CMOS switch formed by CMOS transistorsthat receive the NAND gate output and an inverter output. The CMOSswitch is turned on when the group indication signal C and the setindication signal D both take a logic “1” level. In this example, whenthe CMOS switch is in the on state, it operates to send an output fromthe penetrating through electrode side to a pad of the SDRAM.

Herein, it is assumed that the SDRAM chip shown in FIG. 6A is used asthe SDRAM D15 and that each of the switch elements SW0 to SW15 has thestructure shown in FIG. 6C.

In this case, as shown in FIG. 6A, the second group indication signalC1SIG of logic “1” and the set indication signal D715 of logic “1” aregiven to the switch element SW15 in the SDRAM D15 of the second group(second chip selection group). Therefore, the switch element SW15 is putinto an on state. On the other hand, among the other switch elements SW0to SW14, the switch elements SW0 to SW7 given the first group indicationsignal C0SIG of logic “0” are in an off state and, further, the switchelements SW8 to SW14 given the set indication signals D08 to D614 oflogic “0” are also in an off state.

As a result, only the switch element SW15 in the SDRAM D15 is turned onso that a data signal DQ can be sent or received between the data signalDQ TSV715 and the pad.

On the other hand, when the SDRAM chip shown in FIG. 6A is used as theSDRAM D7, the first group indication signal C0SIG of logic “1” and theset indication signal D715 of logic “1” are given to the switch elementSW7 from the first ROM1 and the second ROM2. As a result, the switchelement SW7 is turned on so that the SDRAM D7 can send or receive a datasignal DQ through the data signal DQ TSV715. When the SDRAM chip shownin FIG. 6A is used as any one of the other SDRAMs D0 to D6 and D8 toD14, it is also possible to achieve the same operation by setting thegroup indication signals and the set indication signals in the firstROM1 and the second ROM2.

Further, referring to FIG. 6A, resistance elements are connected ascompensation impedance elements between the switch elements SW0 to SW15of the SDRAM chip and the data signal DQ penetrating through electrodesTSV08 to TSV715, respectively. In this case, the resistance elementhaving the largest resistance value is connected between the switchelement SW0 and the TSV08 used by the SDRAMs D0 and D8 located at thenearest position from the logic LSI chip 20 while no resistance elementis connected between the switch element SW15 and the penetrating throughelectrode TSV715 used by the SDRAMs D7 and D15 located at the farthestposition from the logic LSI chip 20. In this example, the resistanceelement having a resistance value of 15 times a penetrating throughelectrode resistance RVIA (RVIA×15) is connected to the switch elementSW0.

With a greater distance from the logic LSI chip 20, a resistance with asmaller value is connected. In the case of this example, the resistanceelement with a resistance value of RVIA×14 is connected to the switchelement SW8 and the resistance elements with resistance values ofRVIA×13 and RVIA×12 are connected to the switch elements SW1 and SW9,respectively.

As described above, the structure of the SDRAM chip shown in FIG. 6A canbe directly applied to the SDRAMs D0 to D15 except setting the firstROM1 and the second ROM2. Therefore, the SDRAMs D0 to D15 can be easilymanufactured by incorporating 16 kinds of resistance elements shown inFIG. 6A into each SDRAM chip. For the overall impedance adjustment, aresistance element may be added also between the TSV715 and the switchelement SW15.

The above-mentioned resistance elements as the compensation impedanceelements each have a trimming function or element (not illustrated) usedfor finely adjusting its resistance value (impedance value).Manufacturing variations in the above-mentioned TSV forming process,bump forming process, and TSV-bump connection process are tested afterthe manufacture of the semiconductor device and, according to theresults of the test, the resistance values of the resistance elementsare finely adjusted by the use of the trimming elements. This makes itpossible to achieve substantially real equi-length interconnections thatrespond to the manufacturing results and that connect between thecontrolled chips stacked in the semiconductor device. The test resultsare stored in third ROMs (not illustrated) incorporated in thecontrolled chips, respectively. The resistance values of the resistanceelements are individually adjusted by controlling the trimming elementsbased on the test results stored in the third ROMs.

In the SDRAM chip shown in FIG. 6B, the chip switch circuit portion CSWCconnected to the control signal CS0/1 VIAC0 and VIAC1 includes theswitch elements SWC0 to SWC15 that are selectively turned on in responseto the group indication signals C0SIG and C1 SIG and the set indicationsignals D08 to D715 from the first ROM1 and the second ROM2. Betweeneach of the switch elements SWC0 to SWC15 and the VIAC0 or VIAC1, aresistance element having a larger resistance value is connected as acompensation impedance element as the corresponding SDRAM chip islocated closer to the logic LSI chip 20 while a resistance elementhaving a smaller resistance value is connected as a compensationimpedance element as the corresponding SDRAM chip is located fartherfrom the logic LSI chip 20. Also in this case, no resistance element isconnected to the switch element SWC15 that corresponds to the uppermostSDRAM 15.

Since the SDRAM chip having these resistance elements can be used aseach of the SDRAMs D0 to D15, the SDRAMs D0 to D15 can be easilymanufactured without increasing manufacturing processes only bydesigning each semiconductor chip to have the respective resistanceelements. That is, when forming the address, clock, and commandthrough-silicon vias (TSVs), resistance elements having theabove-mentioned resistance values may be buried in those electrodes.

As shown in FIGS. 6A to 6C, by preparing all the resistance elementswith resistance values that correspond to the stacked positions of theSDRAM chips over the logic LSI chip 20 and by selecting the resistanceelements in accordance with the stacked positions and the sets (DRAMsets), it is possible to compensate for variations in phase of datasignals DQ input to the logic LSI chip 20. Further, it is also possibleto compensate for variations in phase of clocks, addresses, and commandswith respect to the SDRAM chips. Therefore, it is seen that thesemiconductor device according to the second embodiment of thisinvention shown in FIGS. 5 and 6A to 6C can form a semiconductor devicewith a phase variation compensation function. In other words, byselectively connecting compensation resistances that are complementaryto resistances in through-silicon vias (TSVs) at stacked positions,respectively, to make the resistances in all the through-silicon vias(TSVs) substantially equal to each other, it is possible to equalizephase variations not only in data signals DQ, but also in clocks,addresses, and commands.

Further, by employing the structure in which the stacked SDRAM chips aredivided into the groups (chip selection groups) and the through-siliconvias (TSVs) are each shared by the groups, it is possible to reduce byhalf the load of each SDRAM chip as compared with the case where theSDRAM chips are not divided into the groups.

Referring to FIGS. 7A and 7B, a description will be given about anotherexample of a SDRAM chip serving as a controlled chip in a semiconductordevice according to a third embodiment of this invention. The SDRAM chipshown in FIGS. 7A and 7B also has a phase variation compensationfunction like the SDRAM chip shown in FIGS. 6A to 6C. FIG. 7A is forexplaining compensation resistances for phase variation compensationconnected to data signal DQ TSV08 to TSV715 while FIG. 7B is forexplaining compensation resistances connected to clock/address/commandcontrol signal VIAC0 and VIAC1.

The SDRAM chip shown in FIG. 7A has a structure in which all thecompensation resistances have the same resistance value (herein, equalto a resistance value of a penetrating through electrode resistanceRVIA). When the SDRAM chip is used as an uppermost SDRAM D15, nocompensation resistance is connected, which is the same as in FIG. 6A.Accordingly, when the SDRAM chip is used as the SDRAM D15, a data signalDQ is sent or received between the data signal DQ TSV715 and an internalcircuit of the SDRAM D15 not through any compensation resistance.

When the SDRAM chip is used as a SDRAM D7, a data signal DQ from theSDRAM D7 is output to a pad through one compensation resistance RVIA. Onthe other hand, when the SDRAM chip is used as either one of SDRAMs D6and D14, a data signal DQ from the SDRAM D6 or D14 is output to a padthrough three or two compensation resistances RVIA. Likewise, when theSDRAM chip is used as a SDRAM D0 located closest to a logic LSI chip 20,a data signal from the SDRAM D0 is output through 15 compensationresistances RVIA. Likewise, a data signal from a SDRAM D8 is outputthrough 14 compensation resistances RVIA.

That is, in the SDRAM chip shown in FIG. 7A, each compensationresistance RVIA is connected between adjacent two switch elements, i.e.between SW0 and SW8, between SW8 and SW1, between SW1 and SW9, and soon, but not between the data signal DQ TSV08 to TSV715 and the switchelements SW0 to SW15. As a result, a data signal DQ from the selectedSDRAM chip is output to a pad from the selected switch element throughthe plurality of compensation resistances RVIA (except the SDRAMs D7 andD15). In this case, since the other switch elements are not selected,the compensation resistances RVIA are connected in series between theselected switch element and the pad so that the data signal DQ is outputthrough a total resistance value which is a multiple of the value of thecompensation resistance RVIA. Therefore, with this structure, it is alsopossible to compensate for phase variations like in FIGS. 6A to 6C.

The circuit shown in FIG. 6C can be used as each of the switch elementsSW0 to SW15.

In the SDRAM chip shown in FIG. 7B, it is also possible to achieve acompensation resistance structure available when the SDRAM chip is usedas any one of the SDRAMs D0 to D15. That is, compensation resistancesRVIA are provided outside switch elements SWC0 to SWC7, i.e. on the padside of the SDRAM chip. In this structure, a control signal such as aclock signal, an address signal, or a command signal is supplied fromthe control signal VIAC0 or VIAC1 through the number of compensationresistances RVIA that corresponds to a stacked position and a set (DRAMset) of the selected SDRAM chip. Therefore, with the circuit structureof FIG. 7B, it is also possible to compensate for phase variations ofthe control signal.

Referring to FIGS. 8A, 8B, and 8C, a semiconductor device with a phasevariation compensation function according to a fourth embodiment of thisinvention will be described. The semiconductor device shown in FIG. 8Ahas a structure in which only either one of each of SDRAM pairs formingsets (DRAM sets) and sharing data signal DQ TSVs, respectively, isconnected to the corresponding shared data signal DQ TSV while the otherSDRAM is completely disconnected from the corresponding shared datasignal DQ TSV, thereby not only compensating for phase variations ofdata signals DQ, but also reducing by half the load capacitance of databuses formed by the data signal DQ penetrating through electrodes TSV.This will be explained in more detail. In order to simplify theexplanation, FIG. 8A shows only SDRAMs D15 and D7 among SDRAMs D0 toD15, wherein the SDRAMs D15 and D7 respectively have RLWLON (ReadLatency Write Latency ON) generation circuits 9015 and 907 thatrespectively put the SDRAMs D15 and D7 into an off state for a period ofread latency (RT) or write latency (WT) while put the SDRAMs D15 and D7into an on state for the other period. In the example shown in FIGS. 8Ato 8C, switch elements sa and sb, each having a structure shown in FIG.8C, are provided in each of chip switch circuits CS15 and CS7 of theSDRAMs D15 and D7.

As shown in FIG. 8C, the switch elements sa and sb each comprise a NANDcircuit that outputs NAND of three inputs from the RLWLON generationcircuit 90 (index omitted), a first ROM1, and a second ROM2, aninverter, and a CMOS switch. As a result, in response to a logic “1”level signal (on signal) from the RLWLON generation circuit 90 and alogic “1” level from the first ROM1 and the second ROM2, the CMOS switchis turned on and outputs a data signal DQ from the TSV to the pad side.

In FIG. 8A, it is assumed that the RLWLON generation circuit 9015 of theSDRAM D15 outputs a logic “0” level signal while the RLWLON generationcircuit 907 of the SDRAM D7 outputs an on signal of logic “1”. In thiscase, even if a logic “1” level is received as a second group indicationsignal C1SIG and a set indication signal D715 from the first ROM1 andthe second ROM2, the upper switch element sa in the chip switch circuitCS15 of the SDRAM D15 is held in an off state due to the logic “0” levelsignal from the RLWLON generation circuit 9015. Further, the lowerswitch element sb in the chip switch circuit CS15 is also held in an offstate due to the RLWLON signal of logic “0”. Therefore, the SDRAM D15 isin a state completely disconnected from the data signal DQ TSV715.

On the other hand, the upper switch element sa in the chip switchcircuit CS7 of the SDRAM D7 is given the RLWLON signal of logic “1” fromthe RLWLON generation circuit 907, a second group indication signalC1SIG of logic “0”, and a set indication signal D715 of logic “1” whilethe lower switch element sb in the chip switch circuit CS7 is given theRLWLON signal of logic “1” from the RLWLON generation circuit 907, afirst group indication signal C0SIG of logic “1”, and a set indicationsignal D715 of logic “1”. Herein, since the SDRAM D7 belongs to thefirst group, the first group indication signal C0SIG is logic “1” whilethe second group indication signal C1SIG is logic “0”. Further, the setindication signal D715 is logic “1”. In this state, when the RLWLONsignal of logic “1” is given from the RLWLON generation circuit 907 ofthe SDRAM D7, the lower switch element sb in the chip switch circuit CS7is put into an on state.

Therefore, only the SDRAM D7 is connected to the data signal DQ TSV715while the SDRAM D15 sharing the TSV715 is completely disconnected fromthe TSV715. That is, connection/disconnection of each of the SDRAMs D15and D7 with respect to the data signal DQ TSV715 is determined based onan output of the RLWLON generation circuit 90, i.e. a RLWLON signal.

Referring to FIG. 8B, there is shown a planar structure of a SDRAM chipthat can be used as each of the SDRAMs D15 and D7 shown in FIG. 8A. TheSDRAM chip shown in FIG. 8B comprises data signal DQ TSV08 to TSV715,switch elements SW0 to SW15 that correspond to the switch elements saand sb in the chip switch circuit CS15 or CS7 shown in FIG. 8A, a RLWLONgeneration circuit 90, a first ROM1, and a second ROM2. This structureis the same as that shown in FIG. 6A except that a RLWLON signal isgiven to the switch elements SW0 to SW15 from the RLWLON generationcircuit 90 and, further, the operations of the switch elements SW0 toSw15 shown in FIG. 8B are determined by the RLWLON signal, which is alsothe same as in FIG. 8A. Therefore, explanation thereof is omittedherein.

At any rate, as shown in FIG. 8B, by providing the switch elements SW0to SW15 that operate according to the signal from the RLWLON generationcircuit 90, only either one of each of the SDRAM pairs forming the sets(DRAM sets) and sharing the data signal DQ TSVs, respectively, can beconnected to the corresponding shared data signal DQ TSV while the otherSDRAM can be completely disconnected from the corresponding shared datasignal DQ TSV. Like in FIG. 6A, compensation resistances respectivelyhaving resistance values of (RVIA×15 to 0) are connected between theswitch elements SW0 to SW15 and the data signal DQ TSV08 to TSV715,thereby forming a semiconductor device also having a phase variationcompensation function. It is needless to say that compensationresistances may be provided at the positions shown in FIG. 7A.

In FIG. 8A, only the single data signal DQ TSV715 has been described.However, actually, as described with reference to FIGS. 1 and 3, eachSDRAM chip has 256 penetrating through electrodes and data signal DQbuses to form TSVs.

If the structure shown in FIGS. 8A and 8B is employed for such datasignal DQ buses, there are the following advantages in write and readoperations.

First, the advantages in the write operation will be explained. The loadcapacitance to 256 data signals DQ is reduced by half. Accordingly, theoperating current is reduced and the high-frequency operation isachieved. Further, load capacitance variations of the data buses causedby a capacitance variation of (2±0.5) pF possessed by each DQ pin arealso reduced. Therefore, SDRAM input set-up and hold margin areincreased.

On the other hand, there are the following advantages in the readoperation. Since the DQ load on the SDRAM chip side of the 256 databuses is reduced by half, the operating current is reduced and thehigh-frequency operation is achieved. It is also possible to removecapacitance variations of the data buses. It is possible to removeinterference due to a reflected wave caused by L1 of the SDRAM D15.Logic LSI chip input set-up and hold margin are increased.

Referring to FIGS. 9A and 9B, one example of the RLWLON generationcircuit 90 shown in FIGS. 8A to 8C will be described. The illustratedRLWLON generation circuit 90 comprises a command decoder 91, a latencyregister 93, a RL (Read Latency) output control circuit 95, a WL (WriteLatency) output control circuit 97, and an OR circuit 99. The commanddecoder 91 outputs a mode register signal (MRT), a read signal (RDT),and a write signal (WTT) in response to a chip select (CS) signal, RASB,CASB, and WEB. Herein, the mode register signal (MRT) is a logic “1”level signal indicative of latency operation and the read signal (RDT)and the write signal (WTT) are logic “1” level signals indicative ofread and write operations, respectively.

The mode register signal (MRT) is output to the RL output controlcircuit 95 and the WL output control circuit 97 and also given to thelatency register 93. An address signal A0-A13 is input to the latencyregister 93 and the mode register signal (MRT) indicates a latency modeset at a predetermined bit of the address signal. According to a stateof the predetermined bit indicated by the mode register signal (MRT),the latency register 93 outputs a RL signal or a WL signal. The RLsignal represents the number of cycles (n) from a read command until adata signal DQ is actually read while the WL signal represents thenumber of cycles (n) from a write command until a data signal DQ isactually written.

In response to the RL signal, a clock signal CK, and the read signal(RDT), the RL output control circuit 95 outputs, as a RLWLON signal, aRLON signal indicative of an output period of a data signal DQ throughthe OR circuit 99. In other words, after the number of cycles (n) of theclock signal represented by the RL signal, the SDRAM chip is connectedto the data signal DQ penetrating through electrode (TSV) for a periodin which the RLON signal has a logic “1” level. On the other hand, theSDRAM chip is disconnected from this penetrating through electrode (TSV)for a period in which the RLON signal has a logic “0” level.Accordingly, the load capacitance from this SDRAM chip is in an offstate.

Likewise, in response to the WL signal, the clock signal CK, and thewrite signal (WTT), the WL output control circuit 97 outputs, as aRLWLON signal, a WLON signal of logic “1” through the OR circuit 99 fora write period of a data signal DQ after the number of cycles (n)represented by the WL signal.

In FIG. 9B, one example of the circuit structure of the RL outputcontrol circuit 95 is shown. Since the circuit structure of the WLoutput control circuit 97 is substantially the same as that of the RLoutput control circuit 95 except that it operates in response to thewrite signal (WTT), explanation thereof is omitted herein.

The RL output control circuit 95 shown in FIG. 9B is configured to beadaptable to latency cycles of RL(1) to RL(4) and, in this connection,is provided with four AND circuits that operate in response to RL(1) toRL(4), respectively. The RL output control circuit 95 further comprisesan input-side SR latch that operates in response to the mode registersignal (MRT) and the read signal (RDT), 7-stage flip-flops (FF1 to FF7)that count the clock signal CK after receiving a reset signal RB fromthe input-side SR latch, and a logic circuit that logically processesoutputs RLR1 to RLR7 of FF1 to FF7.

Next, referring also to an internal waveform diagram of the RL outputcontrol circuit 95 shown in FIG. 10, its operation will be described.FIG. 10 shows the case where the number of latency cycles (RL) in a DDR3SDRAM is 1 and the burst length (BL) of a data signal DQ is 4.Therefore, the RL output control circuit 95 shown in FIGS. 9A and 9Bstarts outputting a RLON signal of logic “1” as a RLWLON signal inresponse to an output RLR1 of FF1 that is output when a first pulse ofthe clock signal CK has been counted after a read signal (RDT), and thenoutputs a RLON signal of logic “0” as a RLWLON signal in response to anoutput RLR4 of FF4 indicative of having counted a fourth pulse of theclock signal CK.

Specifically, as shown in FIG. 10, a mode register signal (MRT) takes alogic “1” level in response to a mode register command (MRS) and,simultaneously, a RL(1) signal takes a logic “1” level. In this state,when a read command (READ) is given, the command decoder 91 shown inFIG. 9A outputs a read signal (RDT) so that the input-side SR latchshown in FIG. 9B outputs a reset signal RB to FF1 to FF7. Thus, thereset state of FF1 to FF7 is released.

In this state, FF1 to FF7 count the clock signal CK and produce outputsRLR1 to RLR7, respectively. Among the outputs of FF1 to FF7, the outputRLR1 of FF1 is directly input to the AND circuit which is given RL(1).In response to the output RLR1 of FF1, an output of the AND circuitgiven RL(1) takes a logic “1” level and is output as a RLON signalthrough an output-side OR circuit (through VIA7D in FIG. 10).

The logic “1” level state of the RLON signal continues until the outputRLR4 of FF4 takes a logic “1” level. As a result, the RLON signal shownin the lowermost line in FIG. 10 is output from the RL output controlcircuit 95. On the other hand, when the output RLR4 of FF4 takes thelogic “1” level, the input-side SR latch is put into a reset state.

In this example, since RL(1) is set, an output of the AND circuit givenRL(1) takes a logic “1” level in response to a first pulse of the clocksignal CK after RDT. As a result, a RLON signal of logic “1” is outputfrom the output-side OR circuit. Then, FF1 to FF7 continue to count theclock signal CK and until the output RLR4 of FF4 takes a logic “1”level, i.e. until the burst length (BL) becomes 4, the RLON signalcontinues to have a logic “1” level.

While the RLON signal has the logic “1” level, a data signal DQ is readin a burst fashion from the SDRAM. On the other hand, when the RLONsignal takes a logic “0” level, this SDRAM is disconnected so that nodata signal DQ is output. Accordingly, the load capacitance from thedisconnected SDRAM becomes off so that it is possible to reduce by halfthe load of a data signal DQ.

In the above-mentioned example, the description has been given of thecase where the read write latency ON (i.e. RLWLON) generation circuit isconnected to the switch elements SW of each SDRAM. However, thisinvention is by no means limited thereto, but is also applicable to thecase where an on-die termination (ODT) generation circuit is connectedto chip switch circuits of each SDRAM.

In the above-mentioned embodiments, the description has been given ofthe case where the compensation resistances are provided in each SDRAM,but similar compensation resistances may be provided in the control chip20. In this case, if a compensation resistance equivalent to thecompensation resistance connected to the switch element corresponding tothe SDRAM chip closest to the control chip 20 is connected to each datasignal DQ interconnection, it is possible to constantly maintain animpedance-matched state in a read/write operation in a stackedsemiconductor device.

Industrial Applicability

It is apparent that the basic technical idea of this invention is notlimited to the above-mentioned embodiments but may be modified andchanged without departing from the scope and spirit of this invention.For example, although only the SDRAM chips are described in theembodiments, this invention is not limited thereto. This invention isapplicable regardless of the function of chips and thus is applicable toany structure in which signal lines commonly provided in a plurality ofchips continuously pass through from the uppermost chip to the lowermostchip. Further, the controlled chips (slave chips) are not limited to theSDRAMs and may be, for example, SRAMs or nonvolatile memories. Further,the circuit types are not limited to those disclosed in the embodiments.Although the control chip is disposed at the lowermost position in theembodiments, it may alternatively be disposed at the uppermost position.

A transistor may be a field effect transistor (FET) such as MOS (MetalOxide Semiconductor), MIS (Metal-Insulator Semiconductor), or TFT (ThinFilm Transistor), or a transistor other than FET, such as a bipolartransistor. An NMOS transistor (n-channel MOS transistor) is a typicalexample of a first conduction-type transistor while a PMOS transistor(p-channel MOS transistor) is a typical example of a secondconduction-type transistor. A plurality of systems are incorporated in asystem-in-package. This may be exemplified by a system-in-package inwhich a first system comprising a plurality of DRAM chips as slave chipsand a master chip and a second system comprising a plurality of NANDflash memory chips as slave chips and a master chip are integrallypackaged. As a single system, it may be a system in which DRAM chips andNAND flash memory chips are controlled by a single master chip. Thisinvention is not limited to the above-mentioned memory systems, but isapplicable to the whole range of semiconductor products incorporatingCPU (Central Processing Unit), MCU (Micro Control Unit), DSP (DigitalSignal Processor), ASIC (Application Specific Integrated Circuit), ASSP(Application Specific Standard Product), and the like.

Further, a system-in-package to which this invention is applied isapplicable to a semiconductor device such as MCP (Multi-Chip Package) orPOP (Package-On-Package). In the case of POP, the penetrating throughelectrodes TSV disclosed in the embodiments can be replaced by, forexample, ball bumps that connect between stacked individual packages.

Further, a structure may be employed in which first and secondcontrolled chip groups each comprising a plurality of controlled chipsare disposed on opposite sides of a control chip and are connectedtogether through penetrating through electrodes, respectively.

Further, various combinations or selections of various disclosedelements can be made within the scope of claims of this invention. Thatis, it is readily understood that this invention includes variouschanges or modifications that can be made by a person skilled in the artaccording to the entire disclosure including the claims and thetechnical idea.

What is claimed:
 1. A device comprising: a first semiconductor chipcomprising: a first substrate including a first surface and a secondsurface opposite to the first surface, a first via penetrating the firstsubstrate from the second surface of the first substrate to the firstsurface of the first substrate, a first terminal arranged on the firstsurface of the first substrate and coupled to the first via, a firstcircuit arranged on the first surface of the first substrate, and asecond circuit arranged on the first surface of the first substrate andincluding a first resistor coupled between the first terminal and thefirst circuit.
 2. The device as claimed in claim 1, wherein the firstresistor of the second circuit transmits a first signal between thefirst terminal and the first circuit.
 3. The device as claimed in claim2, wherein the first via of the first semiconductor chip is configuredto convey one of a data signal, a data strobe signal, a command signal,a clock signal, and an address signal, and wherein the first signal isthe one of the data signal, the data strobe signal, the command signal,the clock signal, and the address signal.
 4. The device as claimed inclaim 1, wherein the first resistor is configured to vary a resistancevalue thereof in response to a second signal supplied thereto.
 5. Thedevice as claimed in claim 4, wherein the first semiconductor chipfurther comprises a third circuit being configured to supply the secondsignal to the first resistor of the second circuit.
 6. The device asclaimed in claim 5, wherein the third circuit of the first semiconductorchip includes a memory storing data to generate the second signal. 7.The device as claimed in claim 6, wherein the memory of the thirdcircuit of the first semiconductor chip is a ROM.
 8. The device asclaimed in claim 1, wherein the first circuit of the first semiconductorchip is an input circuit outputting a third signal in response to afirst signal supplied thereto.
 9. The device as claimed in claim 1,wherein the second circuit of the first semiconductor chip furtherincludes an additional resistor coupled to the first resistor, and thesecond circuit is configured to be changeable in a resistance valuebetween the first terminal and the first circuit in response to a secondsignal supplied to the second circuit.
 10. The device as claimed inclaim 1, wherein the second circuit of the first semiconductor chipfurther comprises; an bypass line coupled in parallel to the firstresistor, and a switch circuit configured to make one of first andsecond paths, the first path being made to electrically connect thefirst terminal via the first resistor to the first circuit, and thesecond path being made to electrically connect the first terminal viathe bypass line to the first circuit.
 11. A device comprising: a firstchip comprising: a first substrate including a first surface and asecond surface opposite to the first surface, a first via penetratingthe first substrate from the second surface of the first substrate tothe first surface of the first substrate, a first terminal arranged onthe first surface of the first substrate and coupled to the first via, afirst circuit arranged on the first surface of the first substrate, anda second circuit arranged on the first surface of the first substrateand including a first resistor coupled between the first terminal andthe first circuit, and a second chip comprising: a second substrateincluding a first surface and a second surfaces opposite to the firstsurface, a second via penetrating the second substrate from the secondsurface of the second substrate to the first surface of the secondsubstrate, a second terminal arranged on the first surface of the secondsubstrate and coupled to the second via, a third circuit arranged on thefirst surface of the second substrate, and a fourth circuit arranged onthe first surface of the second substrate and including a secondresistor coupled between the second terminal and the third circuit. 12.The device as claimed in claim 11, wherein one of the first and secondchips is stacked over the other of the first and second chips.
 13. Thedevice as claimed in claim 11, wherein the first via of the first chipand the second via of the second chip are electrically connected to eachother.
 14. The device as claimed in claim 11, wherein the secondresistor of the fourth circuit of the second chip is smaller in aresistance value than the first resistor of the second circuit of thefirst chip, when the second chip is stacked over the first chip.
 15. Thedevice as claimed in claim 11, wherein the second chip is one of avolatile memory chip, and a nonvolatile memory chip.
 16. The device asclaimed in claim 15, wherein the first chip is one of a volatile memorychip, and a nonvolatile memory chip.
 17. A device comprising: a firstchip including: a first substrate including a first surface and a secondsurface opposite to the first surface, a first via penetrating the firstsubstrate from the second surface of the first substrate to the firstsurface of the first substrate, and a first resistor circuit formed onthe first surface of the first substrate and configured to be connectedto the first via when the first chip is selected, and the first viabeing increased in a resistance value by the first resistor circuit whenthe first chip is selected.
 18. The device as claimed in claim 17,further comprising: a second chip including: a second substrateincluding a first surface and a second surface opposite to the firstsurface, a second via penetrating the second substrate from the secondsurface of the second substrate to the first surface of the secondsubstrate, and a second resistor circuit formed on the first surface ofthe second substrate and configured to be connected to the second viawhen the second chip is selected, the second via being increased in aresistance value by the second resistor circuit when the second chip isselected.
 19. The device as claimed in claim 18, wherein a resistancevalue of the second resistor circuit is smaller than a resistance valueof the first resistor circuit, when the second chip is stacked over thefirst chip.
 20. The device as claimed in claim 18, wherein the first viaof the first chip and the second via of the second chip are electricallyconnected to each other.
 21. The device as claimed in claim 17, whereinthe first chip is one of a volatile memory chip and a nonvolatile memorychip.
 22. The device as claimed in claim 1, wherein the first resistorof the second circuit is a compensation impedance element.
 23. Thedevice as claimed in claim 1, wherein the first resistor of the secondcircuit is configured to compensate for an impedance of the first via.24. The device as claimed in claim 1, wherein the first substrate is asemiconductor substrate.
 25. The device as claimed in claim 1, whereinthe first via is a through substrate via.
 26. The device as claimed inclaim 1, wherein the first semiconductor chip is one of a volatilememory chip and a nonvolatile memory chip.
 27. The device as claimed inclaim 1, further comprising: a second semiconductor chip, wherein one ofthe first and second semiconductor chips is stacked over the other ofthe first and second semiconductor chips.
 28. The device as claimed inclaim 27, wherein the second semiconductor chip is one of a volatilememory chip, a nonvolatile memory chip, a control chip, and a logicchip.
 29. The device as claimed in claim 11, wherein each of the firstand second resistors of the second circuit is a compensation impedanceelement.
 30. The device as claimed in claim 11, wherein the first chipis a semiconductor chip and the second chip is a semiconductor chip. 31.The device as claim 17, further comprising: a second chip, and whereinone of the first and second chips is stacked over the other of the firstand second chips.
 32. The device as claimed in claim 31, wherein thesecond chip is one of a volatile memory chip, a nonvolatile memory chip,a control chip, and a logic chip.